The question raised by Ham's testimony is whether NATO powers, first and foremost the United States, are willing to invest the necessary military resources to break the stalemate and topple the regime. Ham acknowledged that it would probably require the insertion of foreign ground forces to decisively turn the tide right now -- the rebels have proven no match for Gaddafi's forces, who have them largely pegged back in their eastern strongholds. He said the U.S. would have to consider whether to send in troops.

But escalating Western direct involvement in Libya remains unlikely, at best, for a number of reasons:

It's patently clear, by now, that Libya is in the throes of a civil war -- even if the majority of Libyans detest Col. Gaddafi, it's patently clear that a sizable minority is passionately committed to his regime and willing to fight for it. The strength of the regime on the ground has been underestimated, and the power of the rebellion overestimated. There's no quick and easy military solution, here.

The U.S. has until now made clear that it sees limited national interests at stake in Libya, envisaging its role as that of supporting a European-led intervention. But the Europeans appear ill-equipped to escalate the air war, much less launch a ground war to topple Gaddafi.

The "pottery barn rule" still applies: If it took a Western ground invasion to topple Gaddafi, the Western powers would be forced to own the outcome, which could be extremely messy. The dynamics among and between the various armed groups that would survive a regime collapse -- from pro Gaddafi militias, tribal formations, and various factions of a rebel army that is anything but coherent -- are barely understood, and there's no real state left with institutions that could absorb and reconcile these groups. It may have been recognized by Italy, France, Qatar and Kuwait as the sole legitimate government of Libya, but the Transitional National Council based in Benghazi does not even pretend to be a truly representative national body. Knocking out the regime now through the application of Western military force would create a vacuum that would very likely suck in foreign troops to maintain order and oversee the building of a new Libyan state from scratch. Sure, President Obama would take some licks domestically if he fails to decisively topple Gaddafi, but he hardly wants to run for reelection having committed U.S. troops to a third nation-building mission in the Muslim world.

UN Security Council Resolution 1973, which provides the legal authority for foreign militaries to protect Libyan civilians, can't be translated into a regime-change operation without jeopardizing the alliance. Key NATO members such as Germany and Turkey oppose escalation, and Ankara is pressing hard for a cease-fire that would require Gaddafi forces to withdraw from besieged cities. Stretching the permissions afforded by Resolution 1973 would also jeopardize future international cooperation on humanitarian interventions. (Russia and China may not have voted for this, but they enabled it by refraining from wielding their veto power at the Security Council; if they believe NATO used the authorization as a pretext to pursue regime-change, they may not easily be persuaded to allow future humanitarian interventions.)

Whatever Arab support exists for the current operations is likely to rapidly erode if it involved sending in foreign troops -- remember, even the rebels themselves loudly opposed that idea in the early days of the rebellion.